Cam Shaft Position Sensor Issue
11-13-2009, 05:37 AM
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I have recently completed replacing the engine and trans in the '99 Tib I bought. I have cleaned up most of the issues caused by the previous owner's abuse but I still have a Check Engine Light that reads 0340 for the Cam position sensor.
When I check at the HMA service site I find instructions that say to probe the signal wire and look for 5V at 800rpm and again at 3000rpm.
Investigation resulted in the discovery that there was no power to the sensor.
So I ran a jumper wire from the ECU relay that is supposed to supply power to the sensor but I still see no signal from the CMP sensor. Is it supposed to be an AC or DC voltage? I assume that it is actually a square wave that averages 5V so it should be AC but I don't know for sure.
If I sue the sensor form the spare engine I get the same results. If I connect the spare sensor to the harness and probe the signal wire while moving the sensor close to and away from metal parts I see a resistance change on the meter from 1.5M to .5M ohm so I think the sensor is functional.
Any suggestions on what to try next would be appreciated.
I assume that the ECU switches to Limp Home Mode when this sensor is offline. Is that true?
By way of background, I swapped in a 1.8L engine and am still using the 2.0 ECU. I swapped the 2.0 Injectors into the 1.8 so the ECU
would be able to control them properly. It looks like all the other sensors are the same so it should work OK. The car runs pretty well and seems to be getting OK mileage but I have not checked the actual mileage yet.
Thank you,
KKrofft
When I check at the HMA service site I find instructions that say to probe the signal wire and look for 5V at 800rpm and again at 3000rpm.
Investigation resulted in the discovery that there was no power to the sensor.
So I ran a jumper wire from the ECU relay that is supposed to supply power to the sensor but I still see no signal from the CMP sensor. Is it supposed to be an AC or DC voltage? I assume that it is actually a square wave that averages 5V so it should be AC but I don't know for sure.
If I sue the sensor form the spare engine I get the same results. If I connect the spare sensor to the harness and probe the signal wire while moving the sensor close to and away from metal parts I see a resistance change on the meter from 1.5M to .5M ohm so I think the sensor is functional.
Any suggestions on what to try next would be appreciated.
I assume that the ECU switches to Limp Home Mode when this sensor is offline. Is that true?
By way of background, I swapped in a 1.8L engine and am still using the 2.0 ECU. I swapped the 2.0 Injectors into the 1.8 so the ECU
would be able to control them properly. It looks like all the other sensors are the same so it should work OK. The car runs pretty well and seems to be getting OK mileage but I have not checked the actual mileage yet.
Thank you,
KKrofft
11-13-2009, 06:43 AM
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Vehicle: 2000 Hyundai Accent
To bench test the cam sensor apply 12vdc to pin 3 and ground pin 1. When you place the sensing end near a metal object pin 2 should become common to ground and when it's pulled away it should go open. I guess this would be considered NPN type or sinking.
11-16-2009, 05:11 AM
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I figured it out! I found that during the swap I had plugged the cam position sensor into the knock sensor harness and vice-versa. CEL is now off
and car runs great. Oddly enough I got 27MPG while it was switched. I hop the mileage stays that good now that it is wired correctly.
KK
and car runs great. Oddly enough I got 27MPG while it was switched. I hop the mileage stays that good now that it is wired correctly.
KK
